Table 2.
CT numbers of five foam blocks of 10 mini‐lung‐phantoms from two clinical CT scanners at three CT dose levels. The mean and standard deviation of CT numbers for each block are averaged values over 10 duplicated mini phantoms.
| Foam block 1 | Foam block 2 | Foam block 3 | Foam block 4 | Foam block 5 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Scanner and dose (CTDIvol) | Mean (HU) | Std Dev (HU) | Mean (HU) | Std Dev (HU) | Mean (HU) | Std Dev (HU) | Mean (HU) | Std Dev (HU) | Mean (HU) | Std Dev (HU) |
| Scanner A routine dose (6.67 mGy) | −896.5 | 1.7 | −843.3 | 1.5 | −774.2 | 2.8 | −695.5 | 1.6 | −350.8 | 3.7 |
| Scanner A low dose (1.99 mGy) | −896.0 | 2.2 | −843.0 | 1.6 | −774.7 | 3.0 | −696.1 | 2.5 | −351.5 | 4.9 |
| Scanner A ultra−low dose (0.1 mGy) | −899.0 | 2.5 | −844.1 | 4.0 | −774.5 | 4.5 | −694.5 | 3.3 | −347.0 | 3.3 |
| Scanner B routine dose (6.71 mGy) | −897.4 | 1.2 | −844.9 | 1.0 | −773.9 | 2.6 | −695.1 | 1.7 | −351.3 | 3.9 |
| Scanner B low dose (2.04 mGy) | −897.4 | 1.5 | −845.0 | 1.2 | −774.3 | 2.5 | −694.7 | 2.1 | −350.9 | 4.1 |
| Scanner B ultra‐low dose (0.29 mGy) | −897.1 | 3.3 | −845.1 | 1.6 | −774.7 | 3.2 | −694.6 | 3.4 | −350.0 | 3.9 |